Enable Custom Exporters

[jeremydvoss]

Based off how auto instrumentation uses the exporter environment variables, I enabled the distro to use the entry points for additional exporters.

[lzchen]

What's the purpose of this feature? Why do we allow users to use other exporters besides azure monitor?

[jeremydvoss]

What's the purpose of this feature? Why do we allow users to use other exporters besides azure monitor?

With our emphasis on using env vars for configuring the distro, it seemed to make sense to use the exporter env vars like how they are used in the auto instrumentation flow. Users may want to export to multiple places or output to the console.

Granted, it is possible to add trace and log exporters after the fact. But this approach would be needed for allowing additional periodic metric readers and seems much more user friendly for the tracing and log cases as well.

Since it is not strictly necessary, we can hold off, but is there a deeper reason for the hesitance?